Automobile and other female fuse assemblies commonly comprise a two-piece assembly heretofore having a box-like housing and an all metal one-piece female fuse secured therein. The female fuse has a pair of spaced apart female terminals which are accessible from one end of the housing where male terminal openings are placed in the housing to correspond to male blade-type terminals. The male blade-type terminals or conductors recently, typically extend from a mounting panel or male fuse block, as there has been a shift in the automotive industry toward the use of male terminal blocks. The female terminals are commonly closely encompassed by the housing walls. The female fuse also includes a fuse link extended, usually unsupported, between the female terminals. The connection or transition between the female terminals and the fuse link begins at the center of one female terminal and extends linearly, from a side view, to the other female terminal, without any lateral movement from a top view. From this top view, the width of the fuse link is typically narrowed to create a fuse blowing portion.
Some female fuses use an additional component with the fuse link, such as a ceramic member, for heat conduction purposes to achieve a desired fuse characteristic. The fuse link and additional component are commonly spaced close to the housing side walls for a reduced volume of used material. The above identified two-piece female fuse assembly, with a one piece fuse, is generally disclosed in U.S. Pat. Nos. 4,570,147 (Ebi), 4,751,490 (Hatagishi), 4,869,972 (Hatagishi), 4,871,990 (Ikeda et al.), and 4,958,426 (Endo). However, there are numerous disadvantages with these and other fuses of this type based on the heretofore mentioned female fuse configurations.
Specifically, when the width of the fuse link is narrowed by cutting into the fuse link, it is very difficult to achieve a width which is consistent across the full length of the fuse blowing portion. The consistency of this width is significant because the width of the fuse blowing portion can be used to control the time delay of the fuse. In addition, the use of a linear fuse link, which starts at the center of the female terminals, limits the length of the fuse link. When linear bends are added to increase the length of the fuse link, without any lateral bends, a substantial amount of surface area is discarded during manufacture, as disclosed in Ebi listed above. The length of the fuse link is significant, as the length can be used to control the resistance and, thus, the current rating of the fuse. However, the configuration in Ebi wastes a significant amount of metal during manufacture in order to increase the fuse link length. Furthermore, the use of an additional component with the fuse link, such as a ceramic member, for heat conduction purposes, increases the cost of the materials, and increases the amount of steps of the female fuse assembly.
As further background information for the present invention, European Patent Application EP 633,592 A1 discloses a fuse that also makes use of a fuse link (fusible portion) that extends linearly between the female fuse terminals, without any lateral bends from a top portion. However, the fuse disclosed in this EP 633,592 A1 has female fuse terminals that each use a single spring member in conjunction with a bottom plate to make a connection with respective male terminals. In such a configuration, the single spring member is the sole source of the force necessary to maintain the required connection forces between the female terminals and the respective male terminals that are inserted therein. In addition, the single spring member on each female terminal is bent in a manner such that only a very small surface area of the spring member actually contacts the male terminal when the male terminal is inserted into the female terminal. As such, the significant portion of the electrical connection between the male and female terminal takes place between the male terminal and the bottom plate. Reference DE 2714797 A1 discloses a male fuse which does have a single linear fuse link bend. However, the fuse link bend does not include a fuse-blowing portion, and does not allow for the rating of the fuse to be modified without significant modifications within the manufacturing process.
In addition, Endo discloses a female fuse and a method of the manufacture thereof. The method of manufacture includes punching steps in order to punch the fuse from a sheet metal 6. The female fuse is punched on the interior of the outer edges of the sheet metal 6. Punching on the interior of the sheet metal 6 causes a significant amount of the sheet metal 6 along the outer edges to be waisted.
The present invention is provided to solve these and other problems.